[PATCH v3 30/35] x86/bugs: Add attack vector controls for spectre_v2_user

David Kaplan
2025-01-08T20:25:59Z

Use attack vector controls to determine if spectre_v2_user mitigation is
required.

Signed-off-by: David Kaplan <david.kaplan@amd.com>
---
arch/x86/kernel/cpu/bugs.c | 7 +++++++
1 file changed, 7 insertions(+)

diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index 430f89a5f66a..c1b60ffa3218 100644
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -1614,6 +1614,13 @@ spectre_v2_user_select_mitigation(void)
spectre_v2_user_stibp = SPECTRE_V2_USER_STRICT;
break;
case SPECTRE_V2_USER_CMD_AUTO:
+ if (should_mitigate_vuln(X86_BUG_SPECTRE_V2_USER)) {
+ spectre_v2_user_ibpb = SPECTRE_V2_USER_PRCTL;
+ spectre_v2_user_stibp = SPECTRE_V2_USER_PRCTL;
+ } else {
+ return;
+ }
+ break;
case SPECTRE_V2_USER_CMD_PRCTL:
spectre_v2_user_ibpb = SPECTRE_V2_USER_PRCTL;
spectre_v2_user_stibp = SPECTRE_V2_USER_PRCTL;
--
2.34.1